// Copyright 2017 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef CC_TREES_CLIP_EXPANDER_H_
#define CC_TREES_CLIP_EXPANDER_H_

#include "cc/base/cc_export.h"
#include "ui/gfx/geometry/rect.h"

namespace cc {

class PropertyTrees;

class CC_EXPORT ClipExpander {
public:
    explicit ClipExpander(int filter_effect_id);
    ClipExpander(const ClipExpander& other);

    bool operator==(const ClipExpander& other) const;

    bool operator!=(const ClipExpander& other) const { return !(*this == other); }

    // Maps "forward" to determine which pixels in a destination rect are affected
    // by pixels in the given source rect.
    gfx::Rect MapRect(const gfx::Rect& rect,
        const PropertyTrees* property_trees) const;

    // Maps "backward" to determine which pixels in the source affect the pixels
    // in the given destination rect.
    gfx::Rect MapRectReverse(const gfx::Rect& rect,
        const PropertyTrees* property_trees) const;

    // The id of the effect node in whose transform space the expansion happens.
    int target_effect_id() const { return target_effect_id_; }

private:
    int target_effect_id_;
};

} // namespace cc

#endif // CC_TREES_CLIP_EXPANDER_H_
